A call center is a complete integrated information service system that is operated by a company according to Computer Telephony Integration (CTI), a communication network, and a computer network. Common call center numbers include 10086, 114 and 95555. Generally, a call center provides layered services on the basis of service levels. Layered services are differentiated services that are provided for customer groups at different levels. By means of layered services, the call center supports customer group so as to provide green service paths for VIP customers and business customers.
The key technique for implementing layered services is to group customers, and specifically, to group existing customers to various types of customer groups according to their consumption capability and lifetime value. Different customer groups correspond to different levels. Each type of customer group is further divided into different level groups. In practice, a customer is placed in a call queue corresponding to the customer group it belongs to. Take the call queues of the China Mobile operator for example. The call queues include VIP queue, GoTone queue, M-Zone queue and other queues, as shown in FIG. 1, where the level descends in order of VIP queue, GoTone queue, M-Zone queue and other queues. Each call queue is further divided into different level groups. For example, the VIP queue is divided into a diamond level group, a gold level group, a silver level group and a common level group.
The throughput rate of a call queue means the throughput within n seconds of waiting, where different customer groups correspond to different n values. After the expected throughput rate and the minimum throughput rate are set for each call queue, the call center calculates the real-time throughput rate of the call queues on a timed basis so as to determine the priority of call routing according to a set policy in real time. Specifically, the system determines whether the throughput rate of the call queue of the highest priority meets the requirement. If the requirement is not met while a customer is waiting in the call queue, the system first routes the call of the customer waiting in the queue. If the throughput rate of the call queue of the highest priority meets the requirement, the system determines whether the throughput rate of the call queue of the second highest priority meets the requirement and so on. In FIG. 1, if the throughput rate of the VIP queue does not meet the requirement, the call center serves customers in the VIP queue first and continues to route customers in the next level call queue when the throughput rate of the VIP queue meets the requirement.
This customer group based layered service solution guarantees that a higher level customer group is served prior to a lower level customer group. However, because the call center always chooses customers from the head of a queue, it is possible that a low level customer in one call queue should fail to be served all the time in a specific customer group. For example, in FIG. 1, when the call center chooses customers in the VIP queue, diamond level customers that are lined at the head of the queue are chosen in precedence. When a new VIP customer joins, the newcomer is inserted into the queue according to its level. For example, when a gold level VIP customer comes, the gold level VIP customer is inserted into the gold level position in the queue. The system chooses the gold level, silver level and common level customers in turn after all diamond level customers are served. If there are diamond or gold VIP customers all the time, calls of silver and common customers will not be routed despite their long-time waiting.
In view of this, to ensure the throughput rate of low level customers in a call queue, an easy solution is to set a queue for each level group and adopt layered services for the queues so as to balance the throughput rates of the queues. As shown in FIG. 2, this solution needs to configure and maintain 14 queues. With this solution, it is necessary to set a queue for each level group. As a result, too many queues have to be configured and it is more complex to monitor the state of each queue. Hence, the solution is hard to implement in practice.